Howdy, saturday just gone i hopped in my car on the way home from work and as it warmed up it hit the red on the temp gauge, the light on the dash came on for overheating aswell, then dropped straight back down to its normal cruising temp (just before the n on normal) btw its a ea spac. Anyway it consistently did this every time on the first warm up it would get up to the red. I changed the thermostat with another one i had around and it started fluctuating during driving all the time reaching about 3/4. also while it was getting this hot there was a really loud bubbling sound coming from the radiator and resivour, and it was starting to leak from the top radiator hose from the pressure. Today i replaced the upper and lower thermostat housing, thermostat, temp sender for the gauge, top rad hose, gave it a flush (lots of brown rust looking crap came out, not heaps but it was noticeable, inside all the cooling parts is coated with this brown rubbish. i also replaced the cap cause the old one was looking a bit sad. Anyway just took it for another drive, it did the same hitting the red then settling down and it didnt fluctuate this time. Im hoping its not a head gasket, its not missing and it has no flat spots, no oil in water or vise versa, the only thing left that i can think of is that maybe the radiator is blocked (while i was filling it back up with coolant, it was making wierd bubbling sounds and i would have to wait for the water to drop before i could continue topping up), or the water pump. Does anyone have any ideas before i go out and get a new radiator? ive felt over the radiator and the bottom feels slightly cooler than the top but apart from that im stumped. any help would be greatly appreciated

cheers

chris

well the bottom should be cooler then the top for staters but with you problem it could be a bad signal along the wiring apart from that im lost and confussed as well if its doin it at first start up it would have to be wiring as the engine is cold hence coolant is cold

just took it for a longer drive, its only fluctuating up to half instead of hot, apart from the initial all the way up to full. I dont think its a wiring thing, cause when it gets right up to hot you can hear the coolant boiling/bubbling but then it drops down after a couple of seconds and its all good, going to pick up another radiator tomorrow, i flushed the hell out of the one thats in the car now and the water is taking a bit longer than it should to get through to the other side so id say the bottom half is full of silt. im starting to wonder if my water pump is playing up to because once the thermostat opens i hear this wierd swishing sound from the general area of the water pump, it almost sounds like a belt not sitting right but the noise isnt there at first start, i think its posessed lol

heres hopeing that a nother radiator will fix the prob, if not ill try the water pump

bought a brand spankin new radiator today, it no longer hits the red but its still fluctuating between half and the first bar on the gauge, doesnt matter if its under load, on the highway, up a hill or what not. Could it be the headgasket? ive started it and put my finger over the overflow hose and there is no pressure escaping (read that somewhere to test for headgasket going and blowing gas into the cooling system).

im completey stumped ive spent about 500bux so far and the damn thing is still fluctuating

after reading all that i still think it has got to do with the thermostat so id remove it and run the car with out it to see if it still does it, because by the sound of it faulty thermostats are very common(happened to me twice)

mine started doing that before my heater core blew up. check that too.